dm integrity: remove sector type casts

Since the commit 72deb455

 ("block:
remove CONFIG_LBDAF") sector_t is always defined as unsigned long
long.

Delete the needless type casts in printk and avoids some warnings if
DEBUG_PRINT is defined.

Signed-off-by: Mikulas Patocka <mpatocka@redhat.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>